March 2012 – Triangle Lake Investigation RESULTS: participants were not exposed to 2,4-D at levels that are expected to cause adverse health effects

(1) None of the urine samples contained atrazine or its metabolites at a concentration above the analytical limit of detection. Therefore, there was no evidence of recent exposure to atrazine at the time of testing.

(2) The concentrations of 2,4-D in urine samples from the EI participants were compared to a national sample from the National Health and Nutrition Examination Survey (NHANES) for people 6 to 59 years old. Based on this comparison, the fraction of the EI participants above the NHANES 75th percentile was higher than expected. This suggests an increased exposure relative to the rest of the United States.

(3) Despite an apparent greater exposure than the US population, these data indicate that, at the time of testing, the participants were not exposed to 2,4-D at levels that are expected to cause adverse health effects.